Metabolomics is the quantitative measurement of all (or a certain percentage of all, e.g., most) low-molecular-weight metabolites in an organism at a specified time under specific environmental conditions. Metabolites are the end products of cellular processes and their concentrations reflect the functional status of the organism and thus they are closely related to the observed phenotype. Perturbations in biological pathways can amplify the concentration changes of metabolites, making small molecule metabolites very attractive biomarkers of disease detection. The goal of metabolomics is to discover detectable, quantifiable metabolites—e.g., a panel of markers—that serve as evidence of the presence or stage of disease. Thus, by studying metabolic profiles of individuals with certain diseases and conditions, it is the goal of metabolomics to identify panels of metabolites that serve as an effective tool for disease diagnosis, biomarker screening, and characterization of biological pathways.
Two of the most prominent technologies for metabolite detection and quantification are nuclear magnetic resonance (NMR) and mass spectrometry (e.g., coupled to liquid chromatograph—LC-MS, gas chromatograph—GC-MS or direct analysis-DESI, DART). Mass spectrometry identifies and quantifies metabolites after they have been separated from the mixture, e.g., via high performance liquid chromatography (HPLC).
A biological sample is a highly complex mixture with many components. Extraction, detection, identification, and quantification of each of a panel of specific metabolites from biological samples is not a straightforward task. Furthermore, it is important that protocols be well-established in order to accurately and reproducibly extract, identify and quantify a panel of metabolites in a biological sample obtained from a subject. This is particularly important where the purpose of the analysis is the evaluation of a disease diagnostic—variations in how the sample is handled, processed, and analyzed, as well as variations in how the system is calibrated, can affect the result.
There is a need for an automated analytical system that can be used in a clinical setting to extract, identify and quantify a panel of metabolites, e.g., for evaluation of a metabolite-based diagnostic at an accuracy and precision sufficient to maintain an acceptable sensitivity and specificity.